Known pedometers are designed to count the walking steps of a user, for instance, according to the detection signal of an acceleration sensor worn by the user (see JP2010-71779A, for instance). In a known walking assist device, the detection signal of a contact sensor for detecting the contact of the sole of the foot of the user is used for counting the walking steps of the user (see JP2012-205826A).
A pedometer using an acceleration sensor or a contact sensor for detecting the walking steps of the user may be able to count the walking steps of a non-handicapped person, but may be unable to correctly count the walking steps of a handicapped person with an irregular gait. To overcome this problem, it was proposed to produce a differential angle signal from the right hip joint angle signal and the left hip joint angle signal obtained by a right angular position sensor and a left angular position sensor, respectively, and the count of the walking steps of the user is computed from the differential angle signal (see JP5758028B).